It is well known in the prior art that in order to increase the penetration of a projectile of a certain weight it is necessary to increase the length-to-diameter ratio of the projectile. The Montier et al. U.S. Pat. No. 4,616,569 describes an armor-penetrating projectile having a substantial length-to-diameter ratio and density. In the projectile described in this patent, there is provided an inner member of greater strength and elasticity than the outer member. The inner member is inserted in a bore extending through the projectile.
It is also known in the prior art to provide a lubricant for a projectile to reduce friction when penetrating armor. The Kelson U.S. Pat. No. 4,239,006 discloses a sabot for firearms which is made from a thermoplastic resin containing finely divided lubricant fillers which engage the periphery of the cartridge. The resin provides a lubricant for the cartridge as it passes through the armor. The Gilbert U.S. Pat. No. 4,112,846 discloses an armor-piercing incendiary projectile wherein the incendiary material provides both cushioning and lubrication for the penetrator. U.S. Pat. No. 4,428,295 discloses a high density shot which is composed of two metal powders, one being more dense than lead and the other being flowable upon compaction to serve as a binder for the shot.
While the prior art devices suggest the need for increasing the length-to-diameter ratio of projectiles to increase their armor penetrating ability and, while the prior art also discloses structure for self-lubricating penetrators, there are no projectiles presently available which can achieve the degree of penetration possible with the presently disclosed projectile which has a length-to-diameter ratio greater than 20 without any sacrifice of additional weight and still maintaining sufficient strength and stability to pierce multi-layered armor. In addition, the penetrator is provided with self-lubricating and/or drag reducing means which facilitates the passage of the penetrator through the multi-layered target containing ceramic.